batteries
quantity 33 (34?) Saft "STM 5-200" flooded nickel iron batteries with proprietary formula
http://en.wikipedia.org/wiki/Nickel%E2%80%93cadmium_battery#Vented_cell_batteries
http://www.evdl.org/docs/STM5-180tech.pdf
forum post: http://www.evdl.org/archive/index.html#nabble-td420847
Hi Walt,
According to Wikipedia, the TEVan came equipped with flooded Ni-cads, or nickel-iron batteries and then later there were "advanced" lead-acids and even some NiMH batteries. The two responses I've seen to your note seem to be making different presumptions about the chemistry of your pack and (obviously) the answer depends on that quite a bit.
I've heard that flooded Ni-Cads can be killed by the accidental addition of even a miniscule amount of acid. On the other hand, the nickel-iron cells have a reputation of being nearly indestructable. I'd be curious to know if anyone on the list has any experience with nickel-iron cells being sensitive to contamination from acid.
Anyway, presuming you have flooded alkaline cells of some type, a possible explanation for the behavior of your batteries would be said contamination. Did you use watering equipment that had previously been used on lead-acids?
Best, Joe
In reply to this post by Mark Dutko I have an electric G-van (converted GM van) and it has a 216v string of 34 air-cooled STM-5-200's. I can't find any data on these on Saft's site, but they seem similar to the 180's. They also have a large "PSA" molded into the plastic tops across from "SAFT". I assume they were made for PSA (Peugeot/Citroen). The "STM-5-200" is stamped into the top of the case permanently on each battery. There is no discernable date code I can see, but they look to be about as old as the van (1990).
Here is a crappy cell-phone pic: http://ingineerix.com/pic/?stm-5-200
Everything seems ok with this pack, and I've done 20 miles so far without them seeming to be near end of charge. I'll keep increasing my mileage over time to ascertain what my real range is.
The charger that came with the van is an enormous LaMarche 60a charger, which is microcontroller-based and seems to have been programmed for "Saft NiCd profile" according to what is labeled on the charger.
The pack is equipped with a watering system that consists of 3 water "loops", one loop with 12 batteries, and 2 loops with 11 in it. The 3 loops end in some sort of catalyst block filters that I assume are responsible for neutralizing the electrolyte should it vent too much. The beginning of the loops have fill ports with an auto-sealing valve system.
The electrolyte level seems "normal" (up to the bottom of the caps, and the first time I did a "maintenance" charge, a little water appeared out of each of the catalyst filters.
I'd love to hear more about your MRE-180 watering procedure if you care to share, as it's probably pretty close to what these need!
Thanks!
-Phil